Her mother planned the dinner party, ordering an Italian feast big enough to feed 16 swimmers and five coaches. That would have been enough to make Rachel Bootsma happy, but her coaches went one step further to celebrate Bootsma’s return to Minnesota as a member of the University of California swim team.

They arranged for a limousine to deliver the team to the Monday night dinner at the Bootsma home in Eden Prairie. “I wasn’t sure how it was going to get out of our cul-de-sac, but it did,’’ said Jan Bootsma, Rachel’s mother. “Rachel has been looking forward to this weekend ever since she started school last year. We all have.”

The limo ride and dinner were merely a prelude to the main attraction: the NCAA women’s swimming and diving championships, which began Thursday in the University of Minnesota Aquatic Center pool where Bootsma first discovered how good she could be. The 2012 Olympian — now a sophomore at Cal — helped the Golden Bears to a fifth-place finish in the 400-yard medley relay and swam in the preliminaries of the 200 freestyle relay, which finished second. Friday, she will attempt to defend her NCAA title in the 100 backstroke.

That championship wrapped up an outstanding freshman season for Bootsma, who won a gold medal at the London Games when she raced in the preliminaries for the victorious U.S. 4x100-meter medley relay. Her second year at Cal has presented new challenges, but she enters the NCAA meet in good form. Bootsma won her second Pac-12 title in the 100 backstroke earlier this month in 51.19 seconds and is seeded fourth in a strong NCAA field.

Parents Jan and Rob Bootsma — and other family members and friends — put on their Cal team gear Thursday and sat in the middle of a hearty Golden Bears cheering section. They had watched from those bleachers many times before, as Rachel won club meets and high school state titles at the Gophers’ pool. Adding some NCAA success to that scrapbook, Rachel said, has been on her mind since she learned last year that the meet would be on the U campus.

“I’ve been swimming there since I was eight or nine years old,” said Bootsma, 20, who also will compete in the 100 and 200 butterfly and on Cal’s relays at the NCAAs. “We’d have three or four big meets there every year during my club career, so I know that pool really well.

“I have a lot of good memories there, and some good, fast swimming. It’s going to be fun. I’m really, really excited to be in my home pool.”

Cal coach Teri McKeever is excited for her. Though Bootsma said her results during the dual meet season weren’t as good as she wanted, McKeever praised her masterful handling of her freshman year and her determination to work through obstacles this season.

“She really did a wonderful job last year,” McKeever said. “She had a few more challenges as a sophomore, but I’m just as proud of her. She’s done a really, really great job of learning from each experience and not trying to make this year last year. She just tries to be her best, day in and day out.”

This season has been fun, Bootsma said, though she has put in an enormous amount of work. She made some minor adjustments to her stroke, and it took lots of time for the strides she made in practice to show up in her racing.

She also found that different things were expected of her. As a rookie, Bootsma said, she got to spend the year learning from others; now, she is expected to help teach younger swimmers the ropes, even as she came to understand just how green she still was. And at Cal, where the roster includes four other Olympians and two world champions, it’s impossible to take it easy in practice even for a moment.

“You come back [after freshman year] thinking you know everything, and you don’t know anything at all,” Bootsma said, laughing. “It’s a very different dynamic, having the responsibility to teach when you’re still learning yourself.

“When the people next to you in practice have Olympic medals, there is never a time when you’re not giving 100 percent. It does take a toll mentally, emotionally and physically. But ultimately, that makes us a way better team.”

And ultimately, Bootsma said, she has found satisfaction in meeting the challenge. She is trying to evolve beyond the backstroke; McKeever said Bootsma does not get enough credit for being an all-around swimmer, even after she placed third in both the 100 and 200 butterfly at the Pac-12 meet. Bootsma also was part of two winning relay teams at the conference championships.

After starting the NCAA meet with a celebration, she hopes to end it with one, too. “I’ve learned a lot this year, and I’ve grown a lot, in and out of the pool,” Bootsma said. “The Pac-12 meet showed I’m moving in the right direction. I know there’s more in the tank.”